[Snek] [keith-packard/snek] c600b0: Add op code for 'return.

[Keith Packard]

  Branch: refs/heads/master
  Home:   https://github.com/keith-packard/snek
  Commit: c600b0be79fa8342d808c67ffdfbb108521131cf
      https://github.com/keith-packard/snek/commit/c600b0be79fa8342d808c67ffdfbb108521131cf
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-11-28 (Thu, 28 Nov 2019)

  Changed paths:
    M snek-code.c
    M snek-gram.ll
    M snek.h

  Log Message:
  -----------
  Add op code for 'return.

This is just short-hand for 'branch to end of function', but avoids
needing to patch the value after compiling the function.

Signed-off-by: Keith Packard <keithp at keithp.com>


  Commit: 40d8f1c35769ca9ffee2a1ed4675dfc9a8caa981
      https://github.com/keith-packard/snek/commit/40d8f1c35769ca9ffee2a1ed4675dfc9a8caa981
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-11-28 (Thu, 28 Nov 2019)

  Changed paths:
    M ports/snekboard/ao-pins.h

  Log Message:
  -----------
  ports/snekboard: Stop using AO_SNEK_PWM_RAMP_STEP

The hardware design has been fixed to keep the 3.3V rail solid during
9V power draw changes by disabling the 9V regulator when the input to
the 3.3V regulator drops below 3.75V.

Signed-off-by: Keith Packard <keithp at keithp.com>


Compare: https://github.com/keith-packard/snek/compare/55e8839cc287...40d8f1c35769